TABLE OF CONTENTS. 



Page. 



Preface \' 1 1 



Table of contents X 1 11 



List of illustrations X X \' 



Order I. Tanaioidea or Chelifera '. ."! 



Family I. Tanaidie : 4 



Genus 1 . Pancolus 5 



Pancolus californieusis 5 



Genus 2. Tanais 7 



Tanais U iricatus 7 



i-avolinii 8 



alascensis 10 



robustus 11 



normani 14 



Genua . 3. Cryptofope 16 



Cryptocope arctica 16 



Genus 4. Lepto^nathia 17 



Leptognatbia ca'ca 18 



longiremis 19 



Genus 5. Heterotanais 21 



Heterotanais liniicola 21 



Genus 6. Leptochelia 22 



Leptocbelia forresti 23 



savijinyi 26 



dubia 28 



rapax 30 



filuin 31 



Genus 7. Neotanais 32 



Neotanais americaiius 32 



hastiger 35 



Family II. Apseudid;r 37 



Genus 8. Apseudes 37 



Apseudes espiuosus 38 



gracilis 40 



triangulatus 43 



])ropin(iuus 45 



Genus 9. Parai)seudes 47 



Parapseudes goodei 47 



Genus 10. Typhlai)seudea 49 



Typhlapseudes nereus 49 



Genus 1 1 . Sphy rapus 51 



Spbyrapus malleolus 52 



XIII 



